European Journal of Organic Chemistry

Cover image for Vol. 2015 Issue 25

Early View (Online Version of Record published before inclusion in an issue)

Editor: Haymo Ross, Deputy Editor: Susan Wilkinson

Impact Factor: 3.065

ISI Journal Citation Reports © Ranking: 2014: 13/57 (Chemistry Organic)

Online ISSN: 1099-0690

Associated Title(s): Advanced Synthesis & Catalysis, Asian Journal of Organic Chemistry

VIEW

  1. 1 - 84
  1. Short Communications

    1. C–H Functionalization

      Rhodium-Catalyzed Direct C–H Vinylation of Arenes To Access Styrenes with Vinyl Acetate as a Vinyl Source

      Shu-Tao Mei, Kun Jiang, Nan-Jin Wang, Li Shuai, Yi Yuan and Ye Wei

      Article first published online: 26 AUG 2015 | DOI: 10.1002/ejoc.201500945

      Thumbnail image of graphical abstract

      A variety of styrenes are prepared through RhIII-catalyzed direct aryl C–H vinylation with commercially available and inexpensive vinyl acetate as the vinyl source. This method enables various aromatics including N-sulfonyl ketimines, pyridines, azoles, and amides to be vinylated in moderate to good yields.

  2. Full Papers

    1. C–H Functionalization

      Regioselective Oxidative C–H Phosphonation of Imidazo[1,2-a]pyridines and Related Heteroarenes Mediated by Manganese(III) Acetate

      Mahipal Yadav, Saidulu Dara, Varma Saikam, Mukesh Kumar, Sravan Kumar Aithagani, Satya Paul, Ram A. Vishwakarma and Parvinder Pal Singh

      Article first published online: 26 AUG 2015 | DOI: 10.1002/ejoc.201500984

      Thumbnail image of graphical abstract

      Regioselective synthesis of phosphonylated heteroarenes: A mild, direct, and regioselective C–H phosphonation of imidazo[1,2-a]pyridines and related heteroarenes has been developed. Unlike those previously reported, the present method also works with (NH)-heteroarenes.

    2. Biphenyl-Substituted Phosphines

      Modular Synthesis of Biaryl-Substituted Phosphine Ligands: Application in Microwave-Assisted Palladium-Catalyzed C–N Cross-Coupling Reactions

      Chandani Singh, Jayant Rathod, Vishwajeet Jha, Armen Panossian, Pradeep Kumar and Frédéric R. Leroux

      Article first published online: 26 AUG 2015 | DOI: 10.1002/ejoc.201500962

      Thumbnail image of graphical abstract

      Biaryl-substituted monophosphines have been synthesized by transition metal free ARYNE cross-coupling reactions and subsequent regioselective functionalization through bromine–lithium interconversion. These ligands were employed in palladium-catalyzed C–N bond-forming reactions.

    3. Allylic Oxidation

      MnO2/TBHP: A Versatile and User-­Friend­ly Combination of Reagents for the Oxidation of Allylic and Benzylic Methylene Functional Groups

      Stefano Serra

      Article first published online: 26 AUG 2015 | DOI: 10.1002/ejoc.201500829

      Thumbnail image of graphical abstract

      A simple and user-friendly synthetic procedure for the oxidation of allylic and benzylic methylene groups to the corresponding conjugated carbonyl derivatives is described. The proposed oxidation protocol is based on the combined use of MnO2 and tert-butyl hydroperoxide, and is generally applicable.

  3. Short Communications

    1. Flow Chemistry

      Automated Serendipity with Self-Optimizing Continuous-Flow Reactors

      Zacharias Amara, Emilia S. Streng, Ryan A. Skilton, Jing Jin, Michael W. George and Martyn Poliakoff

      Article first published online: 25 AUG 2015 | DOI: 10.1002/ejoc.201500980

      Thumbnail image of graphical abstract

      Self-optimizing continuous-flow reactors have been used to investigate the reaction of aniline with THF and DMC. High-selectivity profiles were obtained for the synthesis of methylated anilines or N-phenylpyrrolidines. By combining the three components in a single reaction system, a tandem alkylation reactivity leading to diversely alkylated anilines was discovered.

  4. Full Papers

    1. Fused-Ring Systems

      A Novel Synthesis of 2,3-Dihydro-1,3-­methano-1H-indene {(Bicyclo[2.1.1]hexeno)benzene} and Analysis of Its NMR Spectra

      Manfred Christl and Carsten Cohrs

      Article first published online: 25 AUG 2015 | DOI: 10.1002/ejoc.201500831

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      The title compound was prepared from bicyclo[2.1.1]hex-2-ene, and its NMR spectra were analyzed in detail. Previously published 1H-1H coupling constants had to be revised. Surprisingly, the signal of the CH2 groups appear at considerably lower field in the 13C NMR spectrum than that of the benzylic carbon atoms.

    2. Heterocycles

      Total Synthesis of the Marine Natural Product Parazoanthine F by Copper-Mediated C–N Coupling

      Johannes Wefer and Thomas Lindel

      Article first published online: 25 AUG 2015 | DOI: 10.1002/ejoc.201500823

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      CuI/N,N′-dimethylethylenediamine-mediated C–N coupling of a 2,2,4,6,7-pentamethyl-5-sulfonyl-dihydrobenzofuran-protected arginine amide in the microwave was key to the assembly of the N-styrylhydantoin moiety of the marine natural product (–)-parazoanthine F.

    3. Fluorinated Small-Ring Systems

      Synthesis and Physicochemical Properties of 3-Fluorocyclobutylamines

      Anton V. Chernykh, Dmytro S. Radchenko, Alla V. Chernykh, Ivan S. Kondratov, Nataliya A. Tolmachova, Olexandr P. Datsenko, Maxim A. Kurkunov, Sergey X. Zozulya, Yuri P. Kheylik, Katharina Bartels, Constantin G. Daniliuc and Günter Haufe

      Article first published online: 25 AUG 2015 | DOI: 10.1002/ejoc.201500746

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      Hitherto unknown cis- and trans-3-alkyl and 3-aryl-3-fluorocycobutylamines have been synthesised. Comparison of their pKa values with those of the fluorine-free parent compounds showed acidification by about 0.8 units, independent of the stereochemistry, indicating that no through-space interactions occur between fluorine and the amino function.

    4. C–O Bond Activation

      Pincer-Nickel-Catalyzed Cross-Coupling of Aryl Sulfamates with Arylzinc Chlorides

      Jian-Long Tao and Zhong-Xia Wang

      Article first published online: 24 AUG 2015 | DOI: 10.1002/ejoc.201500987

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      A nickel N,N,N-pincer complex effectively catalyzes the cross-coupling of aryl sulfamates with arylzinc chlorides under mild conditions. The reaction is suitable for a wide range of substrates, and tolerates various functional groups.

    5. Intramolecular Guest Exchange

      Calix[6]arene Functionalized at Four Bridges: Conformation and Intramolecular Guest Exchange

      Avia Leader, Norbert Itzhak, Benny Bogoslavsky and Silvio E. Biali

      Article first published online: 24 AUG 2015 | DOI: 10.1002/ejoc.201500873

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      Tetrabromocalix[6]arene 3 underoges an intramolecular guest exchange process involving the unique self-included Boc group and the Boc group on the oppiiosite ring (Boc = tert-butoxycarbonyl).

    6. Peptidomimetics

      Beyond Natural Limitations: Long-Range Influence of Non-Natural Flexible and Rigid β-Turn Mimetics in a Native β-Hairpin Motif

      Matthias Körling and Armin Geyer

      Article first published online: 24 AUG 2015 | DOI: 10.1002/ejoc.201500724

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      β-Turns often function as conformational epitopes that mediate protein recognition. Here the flexibility and turn-inducing capacities of synthetic β-turn mimetics are ranked against each other within the Foldon-derived hairpin environment. Surprisingly, not only rigidified bicyclic β-turn mimetics lead to highly populated hairpins.

    7. C-Arylation

      A Strategy for the Triarylation of Pyrrolo­pyrimidines by Using Microwave-Promoted Cross-Coupling Reactions

      Vanessa Prieur, M. Dolors Pujol and Gérald Guillaumet

      Article first published online: 24 AUG 2015 | DOI: 10.1002/ejoc.201500625

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      Several triarylpyrrolopyrimidines were readily prepared from 4,6-dichloro-2-(methylthio)pyrimidine (2) in excellent yields by using effective cross-coupling reactions. An advantage of this method is its tolerance towards various substituted aryl groups.

    8. Energetic Materials Research

      Energetic Organic Peroxides – Synthesis and Characterization of 1,4-Dimethyl-2,3,5,6-tetraoxabicyclo[2.2.1]heptanes

      Thomas M. Klapötke, Benedikt Stiasny, Jörg Stierstorfer and Charles H. Winter

      Article first published online: 21 AUG 2015 | DOI: 10.1002/ejoc.201500919

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      Energetic organic peroxides – simple, strong and sensitive: This contribution reports on the synthesis of a series of tetraoxabicylclo heptanes which are easy accessible by H2O2 and alkyl-acetyl-acetones. All obtained compounds are highly energetic and sensitive toward mechanical stimuli such as impact and friction. The picture shows the moment of decomposition on a hot copper plate.

    9. Mild OH Protection

      Unexpected Mild Protection of Alcohols as 2-O-THF and 2-O-THP Ethers Catalysed by Cp2TiCl Reveal an Intriguing Role of the Solvent in the Single-Electron Transfer Reaction

      María Jesús Durán-Peña, José Manuel Botubol-Ares, James R. Hanson, Rosario Hernández-Galán and Isidro G. Collado

      Article first published online: 20 AUG 2015 | DOI: 10.1002/ejoc.201500869

      Thumbnail image of graphical abstract

      A set of primary, secondary and benzylic alcohols have been converted into the corresponding THF and THP ethers and tertiary alcohols into the corresponding THF ethers using a catalytic amount of titanium dichloride in good yields and mild reaction conditions.

    10. Fluorescent Probes

      Azadioxatriangulenium: Synthesis and Photophysical Properties of Reactive Dyes for Bioconjugation

      Ilkay Bora, Sidsel A. Bogh, Marco Santella, Martin Rosenberg, Thomas Just Sørensen and Bo W. Laursen

      Article first published online: 20 AUG 2015 | DOI: 10.1002/ejoc.201500888

      Thumbnail image of graphical abstract

      Azadioxatriangulenium or ADOTA has been synthesized with reactive groups for conjugation to amino and thiol groups of biomolecules. The long fluorescence lifetime of the red ADOTA dye allows for new developments in florescence polarization assays, enabled by the detailed account of the synthesis of four ADOTA derivatives presented here.

    11. C–H Amination of Diamondoids

      Intramolecular C–H Amination Reaction Provides Direct Access to 1,2-Disubstituted Diamondoids

      Radim Hrdina, Fabian M. Metz, Marta Larrosa, Jan-Philipp Berndt, Yevgeniya Y. Zhygadlo, Sabine Becker and Jonathan Becker

      Article first published online: 20 AUG 2015 | DOI: 10.1002/ejoc.201500691

      Thumbnail image of graphical abstract

      Intramolecular dirhodium-acetate-catalyzed (1 mol-%) nitrene insertion reactions provide direct access to 1,2-disubstituted diamondoids. This approach was applied to the synthesis of Vildagliptin® (DPP-4 inhibitor) analogues.

    12. Asymmetric Organocatalysis

      Enantioselective Ring Opening of meso-Epoxides with Silicon Tetrachloride Catalyzed by Pyridine N-Oxides Fused with the Bicyclo[3.3.1]nonane Framework

      Algirdas Neniškis and Sigitas Stončius

      Article first published online: 20 AUG 2015 | DOI: 10.1002/ejoc.201500762

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      Chiral Lewis basic catalysts with pyridine N-oxide moieties fused with a bicyclo[3.3.1]nonane framework were used in the enantioselective ring opening of meso-epoxides. 2,4-Diaryl-substituted N-oxide exhibited excellent asymmetric induction with norbornene oxide (96 % ee), whereas less-substituted congener was most effective with alicyclic epoxide substrates (47–88 % ee).

    13. Three-Component Synthesis

      Three-Component Synthesis of 7-Hydroxy-7-polyfluoroalkylhexahydroimidazo[1,2-a]­pyridin-5(1H)-ones

      Marina V. Goryaeva, Yanina V. Burgart, Yulia S. Kudyakova, Marina A. Ezhikova, Mikhail I. Kodess, Pavel A. Slepukhin and Victor I. Saloutin

      Article first published online: 20 AUG 2015 | DOI: 10.1002/ejoc.201500822

      Thumbnail image of graphical abstract

      The construction of polyfluoroalkylated hexahydroimidazo[1,2-a]pyridin-5(1H)-ones was carried out in a one-pot reaction starting from methyl ketones, 1,2-ethanediamines, and fluorinated 3-oxo esters.

    14. Two-in-One Strategy

      Divergent Total Syntheses to Azafluor­anthene and Dehydroaporphine Alkaloids

      Nisachon Khunnawutmanotham, Poolsak Sahakitpichan, Nitirat Chimnoi and Supanna Techasakul

      Article first published online: 20 AUG 2015 | DOI: 10.1002/ejoc.201500866

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      Facile divergent syntheses for azafluoranthene and dehydroaporphine alkaloids are reported by using a biarylsulfonamide-protected amino aldehyde as a common intermediate. The natural azafluoranthenes, triclisine and telitoxine, and an aporphine alkaloid, dehydronornuciferine, were prepared to illustrate the use of this approach.

  5. Short Communications

    1. Sulfur Cations

      Theoretical Study, Synthesis, and Reactivity of Five-Membered-Ring Acyl Sulfonium Cations

      K. V. Raghavendra Rao, Nicolas Caiveau, Rolf David, Ibrahim Shalayel, Anne Milet and Yannick Vallée

      Article first published online: 20 AUG 2015 | DOI: 10.1002/ejoc.201500749

      Thumbnail image of graphical abstract

      The reaction of trimethylsilyl triflate (Me3SiOTf) with γ-alkylthiobutyryl fluorides leads to previously unknown acyl sulfonium cations. These reactive species react both as alkyl-transfer reagents (e.g., with sulfides) and as acylating reagents (e.g., with amines). Such reactivity suggests that the acyl sulfonium derived from methionine may have been able to do the same in the primitive ocean.

    2. Cu-Catalyzed Tandem Reaction

      Construction of Isoquinolin-1(2H)-ones by Copper-Catalyzed Tandem Reactions of 2-(1-Alkynyl)benzaldimines with Water

      Mingliang Zhang, Hui-Jun Zhang, Wenqing Ruan and Ting-Bin Wen

      Article first published online: 20 AUG 2015 | DOI: 10.1002/ejoc.201500908

      Thumbnail image of graphical abstract

      The Cu(OAc)2-catalyzed tandem reaction of 2-(1-alkynyl)benzaldimines with water for the synthesis of isoquinolin-1(2H)-ones is developed. 4-Halogen-substituted isoquinolin-1(2H)-ones can be obtained in good yields simply by including N-halosuccinimides (NXS) in the reaction system. Mechanistic studies are also undertaken.

  6. Full Papers

    1. Nitrogen Heterocycles

      Toward the Synthesis of Tetrazino-­tetrazine 1,3,6,8-Tetraoxide (TTTO): An Approach to Non-annulated 1,2,3,4-Tetrazine 1,3-Dioxides

      Michael S. Klenov, Oleg V. Anikin, Aleksandr M. Churakov, Yurii A. Strelenko, Ivan V. Fedyanin, Ivan V. Ananyev and Vladimir A. Tartakovsky

      Article first published online: 19 AUG 2015 | DOI: 10.1002/ejoc.201500923

      Thumbnail image of graphical abstract

      A novel approach for the synthesis of 6-(tert-butyl-NNO-azoxy)-5-methylthio-1,2,3,4-tetrazine 1,3-dioxide was developed. This compound is likely to be a precursor of tetrazino-tetrazine 1,3,6,8-tetraoxide (TTTO).

  7. Microreviews

    1. Generation of Fluoro Enolates

      Recent Progress in the in situ Detrifluoro­acetylative Generation of Fluoro Enolates and Their Reactions with Electrophiles

      Haibo Mei, Chen Xie, José Luis Aceña, Vadim A. Soloshonok, Gerd-Volker Röschenthaler and Jianlin Han

      Article first published online: 19 AUG 2015 | DOI: 10.1002/ejoc.201500787

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      The high-impact research in the new emerging area of detrifluoroacetylative in situ generation of fluoro enolates is comprehensively presented. The major reaction types featuring in this process include Mannich, aldol, and Michael addition and halogenation reactions. The scientific importance and practical potential of this methodology is highlighted and critically discussed.

  8. Short Communications

    1. Dithiaporphyrins

      Synthesis of β-Substituted meso-Tetraaryl-21,23-dithiaporphyrins by Heck Reaction

      Luana da S. M. Forezi, Ana T. P. C. Gomes, Maria G. P. M. S. Neves, Vitor F. Ferreira, Fernanda da C. S. Boechat, Maria C. B. V. de Souza and José A. S. Cavaleiro

      Article first published online: 18 AUG 2015 | DOI: 10.1002/ejoc.201500812

      Thumbnail image of graphical abstract

      meso-Tetraphenyl-21,23-dithiaporphyrin is selectively monobrominated at one β-pyrrolic position in good yields. This dithiaporphyrin is then functionalized by Heck reaction with styrene derivatives containing different electronic features. The reaction profile is dependent on the electronic characteristics of the styrene derivatives; NBS = N-bromosuccinimide.

    2. Carbon Dioxide Chemistry

      Synthesis of Allyl Carbamates through the Regioselective Domino Reaction of ­Amines, CO2, and Unsymmetrical Allyl Chlorides under Pd Catalysis

      Juewang Cai, Min Zhang and Xiaoming Zhao

      Article first published online: 18 AUG 2015 | DOI: 10.1002/ejoc.201500769

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      With the use of both CO2 (1 atm) and unsymmetrical allyl chlorides, a highly regioselective three-component domino reaction is realized under mild conditions and is used in a Pd-catalyzed allylation process. This method affords new entry to a diverse set of allyl carbamates; dppf = 1,1′-bis(diphenylphosphanyl)ferrocene.

  9. Microreviews

    1. BODIPY Family Diversity

      Postfunctionalization of the BODIPY Core: Synthesis and Spectroscopy

      Noël Boens, Bram Verbelen and Wim Dehaen

      Article first published online: 18 AUG 2015 | DOI: 10.1002/ejoc.201500682

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      In this microreview, the various synthetic postmodification methodologies for functionalization of the BODIPY framework designed and developed by our research groups are comprehensively discussed, together with the electronic spectroscopic properties of the resulting dyes. With these new synthetic methodologies all the pyrrole C-ring positions and the meso-position can readily be substituted.

  10. Full Papers

    1. Peptaibol Synthesis

      Improved Strategy for the Synthesis of the Anticancer Agent Culicinin D

      Michaela Stach, Andreas J. Weidkamp, Sung-Hyun Yang, Kuo-yuan Hung, Daniel P. Furkert, Paul W. R. Harris, Jeff B. Smaill, Adam V. Patterson and Margaret A. Brimble

      Article first published online: 18 AUG 2015 | DOI: 10.1002/ejoc.201500872

      Thumbnail image of graphical abstract

      The anticancer agent Culicinin D, active against breast tumor cells, was synthesised on the solid phase. The resin loading was improved by attachment of first residue to solid-phase via the amine rather than the alcohol. After SPPS and cleavage, the peptide alcohol was formed via an intramolecular O–N transfer reaction. Successful synthesis of several culicinin D analogues demonstrated the feasibility of this new synthetic strategy.

    2. Domino Reactions

      Access to Indene Derivatives by a Sequence of Intermolecular anti-Carbopalladation, Heck Reaction, and Electrophilic Attack

      Martin Pawliczek, Peter G. Jones and Daniel B. Werz

      Article first published online: 18 AUG 2015 | DOI: 10.1002/ejoc.201500868

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      An anti-carbopalladation using enynes and iodoarenes followed by a Heck reaction leads in one step to diene systems with a tertiary hydroxyl group. Acidic conditions allow the arene to attack the emerging carbocation to give indenes.

    3. Anion Binding

      CuAAC Synthesis and Anion Binding Properties of Bile Acid Derived Tripodal Ligands

      Dmitry A. Erzunov, Gennadij V. Latyshev, Alexey D. Averin, Irina P. Beletskaya and Nikolay V. Lukashev

      Article first published online: 18 AUG 2015 | DOI: 10.1002/ejoc.201500835

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      A series of bile acid derived pincer and tripodal ligands that contain anion-binding triazolium and phosphoramide sites were prepared. These compounds efficiently bind inorganic and organic anions to give 1:2 ligand/anion complexes.

    4. Glycan–DNA Interactions

      D- and L-Mannose-Containing glyco-­Oligoamides Show Distinct Recognition Properties When Interacting with DNA

      M. Teresa Blázquez-Sánchez, Filipa Marcelo, María del Carmen Fernández-Alonso, Rafael del Villar-Guerra, Abdelouahid Samadi, F. Javier Cañada, Jesús Jiménez-Barbero and Cristina Vicent

      Article first published online: 17 AUG 2015 | DOI: 10.1002/ejoc.201500740

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      Structural and affinity data have been obtained for different mannose oligoamides when binding to DNA polymers. A β-L-Man ligand (2) binds to poly(dA-dT)2 with a more well-defined structure, consistent with a better affinity. Thus, the placement of cooperative hydrogen-bond donor centres towards the inner region of the minor groove increases the binding affinity for polyAT(dA-dT)2.

  11. Short Communications

    1. Quaternary Stereocenters

      Enantioselective Synthesis of Functionalized Quaternary Stereocenters

      Amarender Manchoju, Rakesh G. Thorat and Sunil V. Pansare

      Article first published online: 17 AUG 2015 | DOI: 10.1002/ejoc.201500985

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      A modular synthesis of functionalized quaternary stereocenters was developed. Key features of the methodology are the stereoselective synthesis of morpholinone-based tetrasubstituted alkenes and diastereoselective Prins reactions of these alkenes. Removal of the amino alcohol portion of the morpholinone provides the target, quaternary stereocenter-containing, building blocks.

    2. Hydrogenation

      Hydrogenation of Aliphatic and Aromatic Nitriles Using a Defined Ruthenium PNP Pincer Catalyst

      Jacob Neumann, Christoph Bornschein, Haijun Jiao, Kathrin Junge and Matthias Beller

      Article first published online: 17 AUG 2015 | DOI: 10.1002/ejoc.201501007

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      An efficient and selective catalytic reduction of nitriles is presented using the commercially available Ru-Macho-BH complex. A variety of aliphatic, aromatic and (hetero)cyclic nitriles including the industrially important adipodinitrile are hydrogenated to the corresponding primary amines. The reaction follows an outer-sphere mechanism.

  12. Full Papers

    1. Thiopyran 1,1-Dioxides

      Base-Induced Cyclization of Propargyl ­Alkenylsulfones: A High-Yielding Synthesis of 4,5-Disubstituted 2H-Thiopyran 1,1-Dioxides

      Ishita Hatial, Joyee Das, Ananta K. Ghosh and Amit Basak

      Article first published online: 14 AUG 2015 | DOI: 10.1002/ejoc.201500633

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      The base-induced cyclization of eneynesulfones to give 2H-thiopyran 1,1-dioxides is described.

    2. Oxygen Heterocycles

      A Rapid Entry to Diverse γ-Ylidenetetronate Derivatives through Regioselective ­Bromination of Tetronic Acid Derived γ-Lactones and Metal-Catalyzed Postfunctionalization

      Nicolas Chopin, Hikaru Yanai, Shinya Iikawa, Guillaume Pilet, Jean-Philippe Bouillon and Maurice Médebielle

      Article first published online: 14 AUG 2015 | DOI: 10.1002/ejoc.201500663

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      The synthesis of a series of γ-ylidenetetronate derivatives is presented. The selective and mild brominations of these derivatives gave useful molecular entities that were employed in several cross-coupling reactions (i.e., Suzuki–Miyaura, Stille, and Sonogashira reactions). Sonogashira-derived materials were utilized in the preparation of 1,2,3-triazole-derived tetronic acids.

    3. Selective Cascade Reactions

      Palladium-Catalyzed 6-endo-Selective Oxycyclization–Alkene Addition Cascades of ortho-Alkynylarylcarboxamides and α,β-Unsaturated Carbonyl Compounds

      Youssef Madich, Rosana Álvarez and José M. Aurrecoechea

      Article first published online: 14 AUG 2015 | DOI: 10.1002/ejoc.201500797

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      In the presence of PdCl2/KI or PdI2 without phosphine ligands or other additives, the cascade reaction between ortho-alkynylarylcarboxamides and methyl vinyl ketone or acrylaldehyde proceeded through a 6-endo-O-cyclization and alkene addition. This reaction occurred without the involvement of competing pathways such as a β-hydride elimination or other cyclization modes.

    4. Sesquiterpene Quinone Synthesis

      Total Synthesis of 3-Oxo- and 3β-Hydroxytauranin via Negishi Coupling of a Bis(ortho-oxy)-Functionalized Benzyl Chloride

      Matthias Göhl and Karlheinz Seifert

      Article first published online: 14 AUG 2015 | DOI: 10.1002/ejoc.201500815

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      The first total synthesis of the sesquiterpene quinones 3-oxo- and 3β-hydroxytauranin (2) was achieved and the originally proposed structure of 3α-hydroxytauranin was revised. The key step of the synthesis is the Negishi coupling of the bis(ortho-oxy)-functionalized benzyl chloride 5 with the alkenyldimethylalane 6.

    5. Supramolecular Chemistry

      Complexations between Oxacalixcrowns and Secondary Ammonium Salts and ­Construction of an Oxacalixcrown-Based [2]Rotaxane

      Hua Liu, Wen-Jing Hu, Yahu A. Liu, Jiu-Sheng Li, Biao Jiang and Ke Wen

      Article first published online: 14 AUG 2015 | DOI: 10.1002/ejoc.201500893

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      A [2]rotaxane R1 (see Scheme) was constructed through a threading-followed-by-stoppering approach. Translocation of the station from the secondary ammonium site to the carbamate site of the thread was achieved through blocking the amino moiety with a bulky Boc group.

  13. Short Communications

    1. Carbonylation

      Construction of Benzimidazoles and Benzoxazoles through the Molybdenum-Mediated Carbonylation of Aryl Halides

      Eshetu Kebede, Ramu Tadikonda, Mangarao Nakka, Bhargavi Inkollu and Siddaiah Vidavalur

      Article first published online: 14 AUG 2015 | DOI: 10.1002/ejoc.201500803

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      The facile and efficient one-pot construction of benzimidazoles and benzoxazoles is described. The reaction proceeds through Mo(CO)6-mediated carbonylation of aryl halides, in which Mo(CO)6 acts as a convenient and safe solid source of carbon monoxide.

    2. Copper Catalysis

      Copper-Catalyzed Synthesis of N-Formyl/Acylsulfenamides and -thiosulfonamides

      Chan Lee, Yu Na Lim and Hye-Young Jang

      Article first published online: 14 AUG 2015 | DOI: 10.1002/ejoc.201500857

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      The copper-catalyzed aerobic coupling of thiols and amides provides a variety of N-formyl/acylsulfenamides and -thiosulfonamides in good yields without over-oxidation of sulfur. The addition of a catalytic amount of a strong base, 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), is the key to promoting this reaction; Ts = tolylsulfonyl.

    3. Diaryliodonium Salt Synthesis

      A Mild and General One-Pot Synthesis of Densely Functionalized Diaryliodonium Salts

      Linlin Qin, Bao Hu, Kiel D. Neumann, Ethan J. Linstad, Katelyenn McCauley, Jordan Veness, Jayson J. Kempinger and Stephen G. DiMagno

      Article first published online: 14 AUG 2015 | DOI: 10.1002/ejoc.201500986

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      One-pot synthesis of complex, unsymmetrical diaryliodonium salts: A mild and general approach to densely functionalized diaryliodonium salts is described. This two-step process has remarkable functional group tolerance, and it is compatible with commonly employed acid-labile protective group strategies.

    4. Organocatalysis

      Enantioselective Synthesis of Medium-Sized-Ring Lactones by Organocatalytic Michael Addition Followed by Reductively Initiated Fragmentation

      Mylène Roudier, Thierry Constantieux, Adrien Quintard and Jean Rodriguez

      Article first published online: 12 AUG 2015 | DOI: 10.1002/ejoc.201500894

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      Chiral, enantioenriched, medium-sized-ring lactones are prepared by an innovative approach. Starting with the organocatalytic Michael addition of cycloalkan-1,3-diones to α,β-unsaturated aldehydes combined with subsequent reductively initiated Claisen fragmentation, 10- and 11-membered-ring natural-product-resembling chiral lactones are synthesized with 91 to >99 % ee.

    5. Fluorescent Dyes

      Bioinspired Fluorescent Dyes Based on a Conformationally Locked Chromophore of the Fluorescent Protein Kaede

      Nadezhda S. Baleeva, Ksenia A. Myannik, Ilia V. Yampolsky and Mikhail S. Baranov

      Article first published online: 12 AUG 2015 | DOI: 10.1002/ejoc.201500721

      Thumbnail image of graphical abstract

      The chromophore of the fluorescent protein Kaede is known to be weakly fluorescent in solution owing to photoisomerization at the arylidene and ethylene double bonds. In this paper, two conformational locks are introduced at these double bonds, which leads to the creation of a novel class of highly fluorescent dyes; FQY = fluorescence quantum yield.

  14. Full Papers

    1. Asymmetric Catalysis

      Synthesis of P-Stereogenic Phosphoramidite and Phosphorodiamidite Ligands and Their Application in Asymmetric Catalysis

      Christian Schmitz, Walter Leitner and Giancarlo Franciò

      Article first published online: 12 AUG 2015 | DOI: 10.1002/ejoc.201500767

      Thumbnail image of graphical abstract

      A series of phosphoramidite (R = OR) and phosphorodiamidite (R = NR2) ligands containing a stereogenic phosphorus atom has been synthesized from chiral Betti bases as amino alcohol building blocks. The new ligands have been applied in three different asymmetric metal-catalyzed reactions, and the interplay between P-stereochemistry, structural features of R, and chirality at the backbone evaluated.

    2. Host-Guest Binding in Macrocycles

      Rationally Designed Supramolecular Organic Hosts for Benzo[a]pyrene Binding and Detection

      Bhasker Radaram and Mindy Levine

      Article first published online: 12 AUG 2015 | DOI: 10.1002/ejoc.201500684

      Thumbnail image of graphical abstract

      A series of 10 organic macrocycles were designed, synthesized, and evaluated for their ability to bind benzo[a]pyrene and facilitate benzo[a]pyrene to BODIPY energy transfer. These results highlight the relationship between structural features of hosts, their overall conformations, and their ability to participate in intermolecular interactions and supramolecular applications.

    3. Pseudopeptides on Au Nanoparticles

      Chiral Gold Nanoparticles Decorated with Pseudopeptides

      Rossana Fanelli, Lorenzo Milli, Andrea Cornia, Alessandro Moretto, Nicola Castellucci, Nicola Zanna, Giulia Malachin, Regina Tavano and Claudia Tomasini

      Article first published online: 12 AUG 2015 | DOI: 10.1002/ejoc.201500549

      Thumbnail image of graphical abstract

      Biocompatible chiral gold nanoparticles (NPs) capped with pseudopeptide foldamers based on an increasing number of L-Ala-D-Oxd units (Oxd = 4-carboxy-5-methyloxazolidin-2-one) were prepared and analyzed with respect to intramolecular H-bonding interactions. According to ECD spectra, the interactions are retained when pseudopeptide foldamers are linked to Au NPs.

    4. Anion-Radical Cyclotrimerization

      Spectroscopic Characterization of 1-­Naphth­yl Isocyanate Anion Radical and of Tris(1-naphthyl) Isocyanurate Atropisomers

      Steven J. Peters, Mark E. Kassabaum, Michael K. Nocella and Robert McDonald

      Article first published online: 11 AUG 2015 | DOI: 10.1002/ejoc.201500863

      Thumbnail image of graphical abstract

      Formation of the 1-naphthyl isocyanate anion radical in [D8]THF results in a rapid cyclotrimerization that generates two diastereoisomers (atropisomers) of tris(1-naphthyl) isocyanurate.

    5. Asymmetric Synthesis

      Synthesis of DOHNAA, a Mycobacterium tuberculosis Cholesterol CD Ring Catabolite and FadD3 Substrate

      Louise A. Stubbing, J. Shaun Lott, Stephanie S. Dawes, Daniel P. Furkert and Margaret A. Brimble

      Article first published online: 11 AUG 2015 | DOI: 10.1002/ejoc.201500698

      Thumbnail image of graphical abstract

      An asymmetric synthesis of DOHNAA, a transcription regulator of the Mycobacterium tuberculosis (Mtb) cholesterol degradation pathway, has been developed. The key alkylation of a Hajos–Parrish dione derivative was found to depend critically on the exact structure of the reaction partners selected. Access to this scaffold will facilitate ongoing investigation of the enzyme pathway and its potential for therapeutic applications.

    6. Cross-Coupling Reactions

      An Air-Stable Nickel(0) Phosphite Precatalyst for Primary Alkylamine C–N Cross-Coupling Reactions

      Sven S. Kampmann, Brian W. Skelton, Duncan A. Wild, George A. Koutsantonis and Scott G. Stewart

      Article first published online: 11 AUG 2015 | DOI: 10.1002/ejoc.201500734

      Thumbnail image of graphical abstract

      The amination reaction between a series of aryl halides and primary alkylamines is described using a new air-stable nickel phosphite based catalyst (BINAP)Ni[P(OPh)3]2.

    7. Olefin Cross-Metathesis

      Olefin Cross-Metathesis: a Versatile Synthetic Reaction for the Design of Janus Liquid Crystals

      Thi Minh Nguyet Trinh, Thanh Tung Nguyen, Cyril Kopp, Pauline Pieper, Virginie Russo, Benoît Heinrich, Bertrand Donnio, Thi Le Anh Nguyen and Robert Deschenaux

      Article first published online: 11 AUG 2015 | DOI: 10.1002/ejoc.201500754

      Thumbnail image of graphical abstract

      New Janus-like liquid crystals were synthesized by olefin cross-metathesis in the presence of the 2nd generation Grubbs catalyst. Linear, chiral, dendritic and nonmesomorphic olefins were used. Smectic C, smectic A, nematic and chiral phases were observed in agreement with the structure and nature of the mesogens.

    8. Phosphane Oxide Reduction

      Lithium Borohydride for Achiral and ­Stereospecific Reductive Boronation at Phosphorus: Lack of Electronic Effects on Stereoselective Formation of Alkoxyphosphonium Salts

      Sulaiman S. Al Sulaimi, Kamalraj V. Rajendran and Declan G. Gilheany

      Article first published online: 10 AUG 2015 | DOI: 10.1002/ejoc.201500521

      Thumbnail image of graphical abstract

      Lithium borohydride is a preferred reagent for achiral and racemic reduction/boronation of phosphane oxide via chlorophosphonium salt (CPS, blue route) and for stereospecific reduction/boronation of diastereomeric alkoxyphosphonium salts (DAPS), derived from CPS and chiral non-racemic alcohol (red route). The new methodology was applied to a series of aryl(methyl)phenylphosphanes and their oxides.

    9. Organocatalysis

      Unmodified Primary Amine Organocatalysts for Asymmetric Michael Reactions in Aqueous Media

      Maria Rogozińska-Szymczak and Jacek Mlynarski

      Article first published online: 7 AUG 2015 | DOI: 10.1002/ejoc.201500913

      Thumbnail image of graphical abstract

      The organocatalytic asymmetric Michael addition of aldehydes to a nitro olefin catalysed by (S,S)-diphenylethylenediamine proceeds in good yields and with good to high enantioselectivities (45–96 % ee). Remarkably high enantioselectivities were observed for the demanding conjugate addition of α,α-disubstituted aldehydes to nitrostyrene (96–98 % ee) in aqueous organic solvent mixtures.

    10. Pyrophosphate-Linked Nucleotides

      On the Synthesis of Oligonucleotides Interconnected through Pyrophosphate Linkages

      Hans A. V. Kistemaker, Nico J. Meeuwenoord, Herman S. Overkleeft, Gijsbert A. van der Marel and Dmitri V. Filippov

      Article first published online: 7 AUG 2015 | DOI: 10.1002/ejoc.201500911

      Thumbnail image of graphical abstract

      We revisit the synthetic methodology for pyrophosphate-interconnected oligonucleotides that relies on reactivity of phosphorodiamidous anhydrides and use an alternative method to synthesize pyrophosphate-interconnected thymidine oligonucleotides.

    11. Drug Synthesis

      Synthesis of Silodosin by Copper-Catalysed C–C Arylation

      Francesco Calogero, Pietro Allegrini, Emanuele Attolino and Daniele Passarella

      Article first published online: 7 AUG 2015 | DOI: 10.1002/ejoc.201500753

      Thumbnail image of graphical abstract

      The synthesis of enantiopure silodosin has been accomplished through CuI-catalysed C–C arylation, regioselective cyanation, and diastereoselective reductive amination.

    12. Pheophorbide a>

      Semisynthesis and in Vitro Photodynamic Activity Evaluations of Halogenated and Glycosylated Derivatives of Pheophorbide a

      Ewa Cieckiewicz, Véronique Mathieu, Luc Angenot, Thierry Gras, Bieke Dejaegher, Pascal de Tullio, Bernard Pirotte and Michel Frédérich

      Article first published online: 7 AUG 2015 | DOI: 10.1002/ejoc.201500387

      Thumbnail image of graphical abstract

      Pheophorbide a (Pha) derivatives were semisynthesized to optimize the photodynamic characteristics of the starting compound; halogenation of the 20-position and glycosylation of the 17c-position were main goals. Glycosylated compounds were identified by LC-SPE-NMR/MS. Photo-triggered in vitro growth inhibitory activities of all new compounds were evaluated using MTT colorimetric assays.

    13. All-Carbon Quaternary Center

      Asymmetric Nitrocyclopropanation of α-Substituted α,β-Enals Catalyzed by Diphenylprolinol Silyl Ether for the Construction of All-Carbon Quaternary ­Stereogenic Centers

      Yujiro Hayashi, Tatsuya Yamazaki, Yuki Nakanishi, Tsuyoshi Ono, Tohru Taniguchi, Kenji Monde and Tadafumi Uchimaru

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500838

      Thumbnail image of graphical abstract

      The diphenylprolinol silyl ether mediated asymmetric nitrocyclopropanation of α-substituted α,β-unsaturated aldehydes with bromonitromethane, followed by base-promoted isomerization affords trans-nitrocyclopropanecarbaldehydes with all-carbon quaternary stereogenic centers with excellent diastereo- and enantioselectivities. The reaction is believed to proceed via an s-trans iminium ion intermediate.

    14. Trichloromethylation

      1,4-Addition of TMSCCl3 to (E)-Fumaric Esters and Thermal Rearrangement of the Adducts to 3,4-Dichloropent-2-enedioates

      Benoit Wahl, Darren S. Lee and Simon Woodward

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500730

      Thumbnail image of graphical abstract

      Mild and efficient conditions for the Michael addition of TMSCCl3 to symmetrical and unsymmetrical fumarates is reported. Using a catalytic initiator in the form of X (X = OAc, Cl, F), the 1,4-addition products undergo a kinetic elimination to yield dichloroalkenes and under thermal rearrangement to form dichloropent-2-enedioates.

    15. Phenol Derivatives

      Synthesis of 2-Arylphenol Derivatives through a One-Pot Suzuki–Miyaura Cou­pling/Dehydrogenative Aromatization Sequence with Pd/C Catalysis

      Kotaro Kikushima and Yuta Nishina

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500723

      Thumbnail image of graphical abstract

      One-pot synthesis of 2-arylphenols starting from 2-iodocyclohexen-1-one derivatives and arylboronic acids through sequential Suzuki–Miyaura coupling/dehydrogenative aromatization with Pd/C catalysis has been developed. In the present method, operationally simple and accessible conditions were used to provide modified phenols as the sole product.

    16. Natural Products Synthesis

      Synthesis of Ganbajunins D and E and the Proposed Structure of Thelephantin D

      Kenshu Fujiwara, Keisuke Kushibe, Takuto Sato, Toshio Norikura, Hajime Matsue, Kunihisa Iwai, Ryo Katoono and Takanori Suzuki

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500722

      Thumbnail image of graphical abstract

      The syntheses of the 2′,5′- and 2′,6′-diacyloxy-p-terphenyl compounds ganbajunins D and E and of the structure proposed for thelephantin D, as well as its regioisomer, were achieved in a divergent manner via a common monoester intermediate. The proposed structure of thelephantin D was, however, found to be different from that of natural thelephantin D on the basis of NMR chemical shifts.

    17. Domino Reactions

      Preparation of 1,2,5-Trisubstituted 1H-Imidazoles from Ketenimines and Prop­arg­ylic Amines by Silver-Catalyzed or Iodine-Promoted Electrophilic Cyclization Reaction of Alkynes

      Xiaorong Zhou, Zheng Jiang, Lexing Xue, Ping Lu and Yanguang Wang

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500704

      Thumbnail image of graphical abstract

      1,2,5-Trisubstituted imidazoles are efficiently prepared from readily available propargylic amines through a AgOTf-catalyzed or molecular iodine-promoted cascade reaction. The presented protocol can be scaled up and the resultant 1,2,5-trisubstituted imidazoles can be converted into fused indeno[1,2-d]imidazoles.

    18. Natural Product Synthesis

      Stereoselective Total Synthesis of the Marine Macrolide Sanctolide A

      Jhillu Singh Yadav, Borra Suresh and Pabbaraja Srihari

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500677

      Thumbnail image of graphical abstract

      The first stereoselective total synthesis of the 14-membered polyketide macrolide sanctolide A was accomplished. The synthesis relied on Yamaguchi esterification and intramolecular dehydrative cyclization reactions to construct the core skeleton of the macrolide.

    19. Sugar-Based Super-Gelators

      Mild One-Step Synthesis of 4,6-Benzylideneglycopyranosides from Aromatic Aldehydes and Gelation Abilities of the Glucose Derivatives

      Fumiyasu Ono, Osamu Hirata, Keiko Ichimaru, Koichiro Saruhashi, Hisayuki Watanabe and Seiji Shinkai

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500658

      Thumbnail image of graphical abstract

      An efficient one-step synthesis of 4,6-benzylidene glycosides from aromatic aldehydes under mild conditions has been achieved. Some of the glucose derivatives synthesised by this method produced clear organo- and hydrogels with thixotropic properties. The critical gelation concentrations of the gels were below 0.1 wt.-%.

    20. Rotaxanes

      A Cholesterol Containing pH-Sensitive Bistable [2]Rotaxane

      Martin Berg, Senada Nozinovic, Marianne Engeser and Arne Lützen

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500657

      Thumbnail image of graphical abstract

      A pH-sensitive bistable [2]rotaxane was synthesized and characterized by NMR spectroscopy and MS/MS. Besides an alkylated triazolium ion, the axle contains a secondary amine that acts as a second pH-sensitive binding site for a crown ether. Depending on the protonation state of this amine function, the crown ether reversibly changes its position by moving between two binding sites on the axles.

    21. Bipyridine Ligand Synthesis

      Modular Synthesis of Elongated Phosphonate Bipyridines

      Markus Braumüller, Dieter Sorsche, Markus Wunderlin and Sven Rau

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500641

      Thumbnail image of graphical abstract

      The synthesis and photophysics of bipyridine (bpy) derivatives L1L3 are described. Application as immobilizable ligands of metal–organic chromophores in solar and photosynthesis cells is enabled by phosphonic ester anchoring groups. Conjugated linkers serve as distance control between bpy and anchor, and show promising effects on photophysics. The solid-state structures of L1 and L2 are shown.

    22. Fluoroalkyl Synthons

      A General Approach towards NH-Pyr­azoles That Bear Diverse Fluoroalkyl Groups by Means of Fluorinated Iminium Salts

      Etienne Schmitt, Grégory Landelle, Jean-Pierre Vors, Norbert Lui, Sergiy Pazenok and Frédéric R. Leroux

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500920

      Thumbnail image of graphical abstract

      Pyrazoles that bear two fluorinated functionalities (identical or different) can be easily obtained by means of activated fluoroalkyl amino reagents.

    23. Photo-Induced Synthesis

      Visible-Light-Induced Meerwein Cascade Reactions for the Preparation of α-Aryl Esters

      Teng-fei Niu, Liang Li, Bang-qing Ni, Mei-jie Bu, Chun Cai and Hui-liang Jiang

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500659

      Thumbnail image of graphical abstract

      A new strategy for the synthesis of α-aryl esters has been reported. This protocol utilizes acrylonitrile as a “bridge molecule” to combine a visible-light-induced Meerwein reaction and a hydrolysis reaction to generate α-aryl esters. This method was also employed for the preparation of oxindoles.

    24. Photolabile Protecting Groups

      Photoactivation of Butyric Acid from 6-Aminobenzocoumarin Cages

      Ana M. S. Soares, Graham Hungerford, Susana P. G. Costa and M. Sameiro T. Gonçalves

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500396

      Thumbnail image of graphical abstract

      Butyric acid was released from new aminobenzocoumarin ester cages in a photoinduced process employing UV/Vis light.

    25. C–H Activation

      Solvent-Free Ruthenium(II)-Catalyzed C–H Activation: Synthesis of Alkenylarylpyrazole Derivatives

      Sanchari Shome and Surya Prakash Singh

      Article first published online: 6 AUG 2015 | DOI: 10.1002/ejoc.201500634

      Thumbnail image of graphical abstract

      The alkenylation of arylpyrazoles and phenyloxazolines by using Ru(MesCO2)2(p-cymene) (Mes = mesityl) as a catalyst and Cu(OAc)2 as an oxidant is reported. Mono- and dialkenylated products can be obtained by controlling the amount of alkene used. The reaction is site selective and takes place exclusively at the ortho position of the heteroaryl moiety.

    26. Selenium Chemistry

      Fused Selenazolinium Salt Derivatives with a Se–N+ Bond: Preparation and Properties

      Pavel Arsenyan, Jelena Vasiljeva, Sergey Belyakov, Edvards Liepinsh and Marina Petrova

      Article first published online: 4 AUG 2015 | DOI: 10.1002/ejoc.201500582

      Thumbnail image of graphical abstract

      Convenient methods for the preparation of stable, fused selenazolinium salt systems with a Se–N+ bond have been developed. The mechanism for the formation of the selenazole cycle was investigated by NMR studies. The ability to form stable inner salts of these compounds was demonstrated. Glutathione peroxidase (GPx) like properties of selenazolopyridinium salts are demonstrated.

    27. Regioselective Protection

      Simultaneous Application of Arylmethyl­ene Acetal and Butane Diacetal Groups for Protection of Hexopyranosides: Synthesis and Chemoselective Ring-Opening Reactions

      Mihály Herczeg, Fruzsina Demeter, Erika Mező, Máté Pap and Anikó Borbás

      Article first published online: 4 AUG 2015 | DOI: 10.1002/ejoc.201500732

      Thumbnail image of graphical abstract

      The reductive cleavage of various arylmethylene acetals in the presence of butane diacetals was studied for the first time. Three reagent systems were used to gain access to either 4-hydroxy or 6-hydroxy glycoside derivatives. With the proper choice of reagents, benzylidene-type acetals can be opened regio- and chemoselectively in high yields.

    28. Fullerene Adducts

      Regioselective Thermal Reaction between Triethylamine and C60 Revisited: X-ray Confirmation of the Pentane-Fused Adduct and in Situ Mechanism Study

      Muqing Chen, Wangqiang Shen, Lipiao Bao, Wenting Cai, Yunpeng Xie, Takeshi Akasaka and Xing Lu

      Article first published online: 4 AUG 2015 | DOI: 10.1002/ejoc.201500814

      Thumbnail image of graphical abstract

      X-ray crystallographic results unambiguously confirm for the first time the pentane-fused structure of adduct 1 obtained from the reaction between triethylamine (TEA) and C60. The successful detection of intermediates (acetaldehyde and diethylamine) involved in the thermal reaction makes the reaction mechanism clear.

  15. Short Communications

    1. Indole Synthesis

      Synthesis of Indoles by Palladium-Catalyzed Reductive Cyclization of β-Nitrostyrenes with Carbon Monoxide as the Reductant

      Francesco Ferretti, Mohamed A. EL-Atawy, Stefania Muto, Mohamed Hagar, Emma Gallo and Fabio Ragaini

      Article first published online: 3 AUG 2015 | DOI: 10.1002/ejoc.201500933

      Thumbnail image of graphical abstract

      Indoles and azaindoles can be obtained by reductive cyclization of β-nitrostyrenes, which can be easily obtained in most cases from cheap nitroalkanes and aromatic aldehydes. The method is effective for the synthesis of both 2- and 3-substituted indoles; Phen = 1,10-phenanthroline.

  16. Full Papers

    1. N-Methyl-O-Glycosyl Amino Acids

      Fluorenylmethoxycarbonyl-Protected O-Glycosyl-N-methyl Amino Acids: Building Blocks for the Synthesis of Conformationally Tuned Glycopeptide Antigens

      Annette E. Buba, Holger Löwe and Horst Kunz

      Article first published online: 3 AUG 2015 | DOI: 10.1002/ejoc.201500929

      Thumbnail image of graphical abstract

      Fmoc-protected building blocks of N-methylated O-glycosyl amino acids, inaccessible so far, have been synthesized by the conversion of Fmoc-O-glycosyl amino acids into the corresponding oxazolidines followed by reductive ring-opening. These N-methyl-O-glycosyl amino acids could be used in solid-phase glycopeptide syntheses under particular conditions.

    2. Allylic Alkylation

      Palladium-Catalyzed Allylic Alkylation Reactions of Glycolates as a Tool for the Synthesis of Functionalized α-Hydroxy Esters

      Alexander Kiefer, Dnyaneshwar Gawas and Uli Kazmaier

      Article first published online: 3 AUG 2015 | DOI: 10.1002/ejoc.201500755

      Thumbnail image of graphical abstract

      Deprotonated tert-butyl glycolates are suitable nucleophiles for Pd-catalyzed allylic alkylation reactions that generate γ,δ-unsaturated α-hydroxy acid derivatives. Stannylated derivatives can be subjected to further modifications.

    3. Arene Diazonium Salts

      Acetamidoarenediazonium Salts: Opportunities for Multiple Arene Functionali­zation

      Bernd Schmidt, Nelli Elizarov, Nastja Riemer and Frank Hölter

      Article first published online: 31 JUL 2015 | DOI: 10.1002/ejoc.201500795

      Thumbnail image of graphical abstract

      Acetamidoarenediazonium salts, accessible from simple acetamidoanilines, are starting points for multiple Pd-catalyzed arene functionalization reactions.

    4. Natural Products Synthesis

      Synthesis, Optical Rotation, and Absolute Configurations of Santinols

      Wen-Ju Wu, Hui-Jun Chen, Jun You, Yikang Wu and Bo Liu

      Article first published online: 31 JUL 2015 | DOI: 10.1002/ejoc.201500758

      Thumbnail image of graphical abstract

      Natural glycerolipids santinols A1 and A2 were synthesized in optically active form by a chiral-pool-based route. The samples confirmed the assigned structures, but it was found that the sign of the optical rotation may reverse if the sample solution is prepared a long time before data acquisition. Assignment of configurations of such molecules from optical rotations must hence be very cautious.

    5. Nitrogen Heterocycles

      Metal-Free Oxidative C–H Amidation of N,N′-Diarylureas with PhI(OAc)2: Synthesis of Benzimidazol-2-one Derivatives

      Jipan Yu, Chang Gao, Zhixuan Song, Haijun Yang and Hua Fu

      Article first published online: 31 JUL 2015 | DOI: 10.1002/ejoc.201500726

      Thumbnail image of graphical abstract

      A simple and practical metal-free oxidative C–H amidation of N,N′-diarylureas has been developed. This protocol uses readily available N,N′-diarylureas as starting materials and inexpensive PhI(OAc)2 as an oxidant without the need for a catalyst, ligand, or the exclusion of air. The method has wide functional group tolerance and provides a new strategy to synthesize N-heterocycles.

    6. Gallium Catalysis

      Hydroarylation of Alkynes with Phenols in the Presence of Gallium Complexes of a Labile N-Ligand: Synthesis of Chromenes

      Mikhail V. Moskalev, Arkadiy M. Yakub, Alexander G. Morozov, Evgenii V. Baranov, Olga V. Kazarina and Igor L. Fedushkin

      Article first published online: 31 JUL 2015 | DOI: 10.1002/ejoc.201500680

      Thumbnail image of graphical abstract

      Gallium complexes with the functionally labile (redox-active) bis-amido ligand dpp-bian serve well as catalysts for the hydroarylation of phenylacetylene. The product of the reaction between phenylacetylene and naphthalen-1-ol undergoes further a catalytic transformation to give chiral chromenes.

    7. Organocatalysts

      An Acid/Base-Regulated Recyclable Strategy for Homogeneous Cinchona Alkaloid-Derived Primary Amine Organocatalysts in Aldol, Vinylogous Michael and Double-Michael Cascade Reactions

      Jingwei Wan, Zhiwei Zhao, Falu Wang and Xuebing Ma

      Article first published online: 31 JUL 2015 | DOI: 10.1002/ejoc.201500566

      Thumbnail image of graphical abstract

      A practical acid/base-regulated recyclable strategy for cinchona alkaloid-derived organocatalysts by means of protonation and deprotonation of primary and tertiary amine groups was developed and applied in asymmetric aldol, vinylogous Michael and double-Michael cascade reactions.

    8. Luminescent Pigments

      First Demonstration of the Applicability of the Latent Pigment Approach to Plastic Luminescent Solar Concentrators

      Sara Mattiello, Alessandro Sanzone, Paolo Brazzo, Mauro Sassi and Luca Beverina

      Article first published online: 24 JUL 2015 | DOI: 10.1002/ejoc.201500554

      Thumbnail image of graphical abstract

      First demonstration of the applicability of the latent pigment approach to plastic luminescent solar concentrators The latent pigment approach enables the straightforward preparation of stable single-layer plastic luminescent solar concentrators based on the otherwise non-emissive and insoluble quinacridone and perylenediimide pigments.

    9. Ribonucleotides

      mRNA Cap Modification through Carb­amate Chemistry: Synthesis of Amino- and Carboxy-Functionalised Cap Analogues Suitable for Labelling and Bioconjugation

      Marcin Warminski, Zofia Warminska, Joanna Kowalska and Jacek Jemielity

      Article first published online: 24 JUL 2015 | DOI: 10.1002/ejoc.201500672

      Thumbnail image of graphical abstract

      A series of amino- and carboxy-functionalised dinucleotide 5′ cap analogues have been synthesised by use of carbamate chemistry. The compounds are suitable for labelling with biotin or fluorescent tags by employment of an in situ NHS activation strategy,

    10. Total Synthesis

      An Efficient Stereoselective Total Synthesis of All Stereoisomers of the Antibiotic Thiamphenicol through Ruthenium-Catalyzed Asymmetric Reduction by Dynamic Kinetic Resolution

      Marc Perez, Pierre-Georges Echeverria, Elsa Martinez-Arripe, Mehdi Ez Zoubir, Ridha Touati, Zhaoguo Zhang, Jean-Pierre Genet, Phannarath Phansavath, Tahar Ayad and Virginie Ratovelomanana-Vidal

      Article first published online: 14 JUL 2015 | DOI: 10.1002/ejoc.201500661

      Thumbnail image of graphical abstract

      An expedient synthesis for the four isomers of the broad-spectrum antibiotic thiamphenicol is described through either a ruthenium-catalyzed asymmetric hydrogenation or a transfer hydrogenation reaction by a dynamic kinetic resolution.

  17. Microreviews

    1. 4′-Selenonucleosides

      4′-Selenonucleosides as Next-Generation Nucleosides

      Pramod K. Sahu, Siddhi D. Naik, Jinha Yu and Lak Shin Jeong

      Article first published online: 8 JUL 2015 | DOI: 10.1002/ejoc.201500429

      Thumbnail image of graphical abstract

      Modified nucleosides have served as valuable resources for therapeutic agents such as antiviral and antitumor agents. Because of several adverse effects of old-generation nucleosides, emergence of a new template of modified nucleosides is highly desirable. This review describes the stereoselective synthesis, conformation analysis, and biological activity of various modified 4′-selenonucleosides.

    2. Organometallic Rearrangements

      Formal Dyotropic Rearrangements in Organometallic Transformations

      Michael F. Croisant, Ryan Van Hoveln and Jennifer M. Schomaker

      Article first published online: 22 JUN 2015 | DOI: 10.1002/ejoc.201500561

      Thumbnail image of graphical abstract

      Organometallic dyotropic rearrangements involve interchange of two groups on a stationary scaffold by breaking and reforming of two σ bonds. They proceed through various different mechanisms and yield a diverse array of products. This microreview traces recent developments and applications of formal dyotropic rearrangements involving both stoichiometric and catalytic amounts of transition metals.

    3. Hydrogen-Transfer Reactions

      Pd-Catalyzed Hydrogen-Transfer Reactions from Alcohols to C=C, C=O, and C=N Bonds

      Jacques Muzart

      Article first published online: 12 JUN 2015 | DOI: 10.1002/ejoc.201500401

      Thumbnail image of graphical abstract

      Highlights and mechanisms of Pd-catalyzed abstracting and borrowing hydrogen transfers from alcohols are presented.

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